1. Field of the Invention:
The present invention relates to an electric rotating machinery and particularly to such a machinery having a wire connector to external wires.
2. Description of the Related Art:
The electric rotating machinery including electric motors and generators are required to have sufficiently insulated and waterproofed connectors to external wires. Particularly, various types of motors used in automobiles for power-steering, power-windows, door locks and so on are expected to be used under various severe conditions. Therefore, the wire connectors used therein must be waterproofed and insulated sufficiently to withstand moisture, rainwater and so on.
FIGS. 4 and 5 show a power supply wire connector of DC motors for automobiles that is constructed in accordance with the prior art.
The power supply wire connector of the DC motor includes a connection box 12 formed in part of a motor housing 10. The connection box 12 has an open top. Inner wall of the connection box 12 has a pair of apertures 14 formed through the motor housing 10 to communicate with the interior thereof. The connection box 12 also includes a pair of terminal fittings 16 which extend into the interior of the connection box 12 through the respective apertures 14. The other end of each of the terminal fittings 16 is connected to the brush of a motor. The pair of terminal fittings 16 extend parallel to each other within the connection box 12 and have a top wider side face 16a directed to the open top. The end of each of the terminal fittings 16 that is placed within the connection box 12 is formed with a caulking pawl 18.
Within the connection box 12, the terminal fittings 16 are connected to a pair of external power supply wires 20 in the following manner.
The power supply wires 20 extend from the outside into the connection box 12. The inner end of each of the power supply wires 20 is caulked by the caulking pawl 18 of the corresponding terminal fitting 16 and soldered to provide a firm connection between the terminal fitting 16 and the power supply wire 20.
After provision of such a firm connection, a hot-melt adhesive 24 functioning as a waterproofing and insulating filler is poured through a nozzle 22 and solidified in the connection box 12. In such a manner, not only the connection between the terminal fittings 16 and the power supply wires 20 is electrically insulated from the surroundings, but also the apertures 14 for the terminal fittings are completely waterproofed to prevent any water from penetrating into the motor housing.
In the aforementioned power supply connection of the prior art, the terminal fittings 16 extend in the connection box 12 so that the top wider side faces 16a thereof are directed upwardly to the open top. Therefore, the wider side faces 16a of the terminal fittings 16 will be perpendicular to the direction of flow of the poured hot-melt adhesive 24 shown by arrow 200 in FIG. 5. As a result, the flow of the hot-melt adhesive 24 will be more resisted by the terminal fittings 16. It is thus difficult for the hot-melt adhesive 24 to flow into the backsides (bottom sides) of the terminal fittings 16.
This tends to create spacings 26 in the backsides of the terminal fittings 16 which have no hot-melt adhesive 24. Such spacings 26 deteriorate the insulating and waterproofing properties in the connection box 12. In addition, the water may undesirably enter the motor housing 10 through the gaps between the terminal fittings 16 and the apertures 14 via the spacings 26.
Further, the soldering material between the terminal fittings 16 and the power supply wires 20 may be undesirably formed into such a configuration as obstructing the down-flow of the hot-melt adhesive 24. This also tends to form the spacings 26 below the terminal fittings 16 to reduce the insulating and waterproofing properties in the connection box 12.